Yup, Dart itself is an ok language (and has improved dramatically in the time I've used it), but the tooling around Dart and Flutter are what make me stay. It's all fairly standard, but complete, and it basically always just works, and the handful of times it doesn't, it's when I've known I'm doing something odd.

The community has lots of great, well built packages, and the Dart and Flutter teams are also quite responsive to the community, and helpful when an issue does arise. I've spent several threads going back and forth with maintainers trying to figure out a bug, and I'm happy to say that every single time we've found a solution.